• SJSU Singular Matrix Database
  • Matrix group: HB
  • Click here for a description of the HB group.
  • Click here for a list of all matrices
  • Click here for a list of all matrix groups


  • Matrix: HB/bcsstk32
  • Description: STIFFNESS MATRIX FOR AUTOMOBILE CHASSIS (MSC NASTRAN) - PATTERN ONLY
  • download as a MATLAB mat-file, file size: 657 KB. Use SJget(509) or SJget('HB/bcsstk32') in MATLAB.
  • download in Matrix Market format, file size: 2 MB.
  • download in Rutherford/Boeing format, file size: 666 KB.

    HB/bcsstk32

    A singular value of A is guaranteed1 to be in the interval pictured by the blue bars around each of the calculated singular values.

    Routine svds_err, version 1.0, used with Matlab 7.6.0.324 (R2008a) to calculate the 6 largest singular values and associated error bounds.
    Routine spnrank, version 1.0, used with Matlab 7.6.0.324 (R2008a) to calculate singular values 14150 to 14155 and associated error bounds.

    HB/bcsstk32

    Matrix properties (click for a legend)  
    number of rows44,609
    number of columns44,609
    structural full rank?yes
    structural rank44,609
    numerical rank 14,152
    dimension of the numerical null space30,457
    numerical rank / min(size(A))0.31725
    Euclidean norm of A 75.194
    calculated singular value # 141523.3943e-005
    numerical rank defined using a tolerance
    max(size(A))*eps(norm(A)) =
    6.3393e-010
    calculated singular value # 141531.153e-012
    gap in the singular values at the numerical rank:
    singular value # 14152 / singular value # 14153
    2.9439e+007
    calculated condition number-2
    condestInf
    nonzeros2,014,701
    # of blocks from dmperm1
    # strongly connected comp.1
    entries not in dmperm blocks0
    explicit zero entries0
    nonzero pattern symmetrysymmetric
    numeric value symmetrysymmetric
    typebinary
    structuresymmetric
    Cholesky candidate?yes
    positive definite?no

    authorR. Cigel, R. Grimes, J. Lewis, E. Meyer
    editorI. Duff, R. Grimes, J. Lewis
    date1986
    kindstructural problem
    2D/3D problem?yes
    SJid509
    UFid54

    Ordering statistics:AMD METIS
    nnz(chol(P*(A+A'+s*I)*P'))4,988,735 5,780,089
    Cholesky flop count9.5e+008 1.4e+009
    nnz(L+U), no partial pivoting9,932,861 11,515,569
    nnz(V) for QR, upper bound nnz(L) for LU14,950,031 11,914,354
    nnz(R) for QR, upper bound nnz(U) for LU30,560,536 23,132,332

    Maintained by Leslie Foster, last updated 24-Apr-2009.

    Entries 5 through 14 in the table of matrix properties and the singular
    value plot were created using SJsingular code. The other plots
    and statistics are produced using utilities from the SuiteSparse package.
    Matrix color plot pictures by cspy, a MATLAB function in the CSparse package.